Thermo-electric regulating system.



G. N. BLANCHARD. THERMO ELECTRIC REGULATING SYSTEM.

APPLICATION FILED DEC-2, I912.

Patented June 1, 1915.

2 SHEETSSHEET l- INVENTOR WITNESSES ATTORNEY G. N. BLANCHARD. THERMOELECTRIC REGULATING SYSTEM.

APPLICATION FILED DEC'Z, 1912. I 1,141,307, PatentedJune 1, 1915.

2 SHEET$SHEET 2.

WITNESSES INVENTOR UNITED STATES PATENT oEEIc GEORGE N. BLANCHARD, OFSAN FRANCISCO, CALIFORNIA, ASSIGNOR OF ONE-HALF TO WILLIAM HENRY BUSCH,JR., OF SAN FRANCISCO, CALIFORNIA.

THERMO-ELECTRIC REGULATING SYSTEM.

To all whom it may concern: I

' Be it known that I, GEORGE N. BLANCH- ARD, a citizen of the UnitedStates, residing in the city and county of San Francisco and StateofCalifornia, have invented certain new and useful Improvements in ThermoElectric Regulating Systems, of which the following is a specification.

The hereinafter described invention relates to an improvedthermo-electric appa ratus for automatically regulatingthe temperatureof an inclosure, but is more particularly designed for use in coldstorage houses, where it is desired to maintain constant the temperatureof the interior thereof at all times, so that perishable articles storedtherein, such as meat, poultry and eggs, will at alltimes be preservedin a temperature varying only a fraction of a degree.

The invention has for its principal object to provide an apparatus ofthe above character which is very sensitive to the changes intemperature, that is, capable of being adjusted to operate within afraction of a degree of temperature, or a wide range of temperature, andwhich is electrically connected to the controlling means'of a supply ofcooling fluid, the electrical connections being made or broken by therise or fall of pressure in the apparatus, which is controlled by therise or fall of the temperature within the room.

The invention consists in a closed system of suitable hollow tubingcontaining a fluid sensitive to the changes of temperature, andhereinafter termed a thermo-system, a mercury tube provided with acapillary bore and formed at its lower end with an inner and outer bulbcommunicating at their lower ends, said bulbs partly filled withmercury, a communication between said hollow tubing and the upperportion of said outer bulb, pressure actuated means connected to saidsystem of tubing and operated by the expansion of the fluid therein, anelectrically operated valve controlling a supply of cooling fluid,electrical connections between said electrically operated valve and saidpressure actuated means, said pressure actuated means making or breakingelectrical contacts to operate said valve to open or close according tothe expansion or contraction of the fluid in said thermo-system.

With the above mentioned and other objects Specification of LettersPatent.

in view the invention consists in the novel construction and combinationof parts hereinafter fully described; illustrated in the accompanyingsheets of drawings, and pointed out in the claims hereto appended; itbeing understood that various changes in the form, proportion, size andminor details of construction, within the scope of the claims heretoappended, may be resorted to without departing from the spirit orsacrificing any i of the advanta es of the invention.

To more ful y comprehend the invention, reference should be had to theaccompanymg sheets of drawings, wherein Figure l is a View in elevationof my improved apparatus, disclosing the electrically operated valvecontrolled brine supply pipe, the thermo-system, the mercury tubeconnected therewith, and the pressure operated device connected to saidthermo-system for controlling the operation of said electricallyoperated valve controlling said brine supply pipe. Fig. 2 is a View indetail of the electric circuit for controlling the operation of theelectrically operated valve and the pressurte actuated arm forcontrolling the circul Referring more particularly to the drawings, thereference numeral 1 designates connected coils of suitable hollowtubing, the coils being of any convenient shape and are adapted tocontain to their full capacity a suitable fluid which is sensitive tothe changes of temperature, preferably alcohol, the fluid when subjectedto warm temperature expanding and creating greater pressure in the coilsthan when it is subjected to a cold temperature and contracts in thecoils.

Connected to the interior of the coils 1 through a suitable coupling 2is a suitable pressure actuated controller, mounted in the usual casing3 and formed with a hollow curved spring arm 4 of the Bourdon type,closed at one end and connected to and co1nmunicating with the coupling2 at its opposite end,

Connected to but insulated from the closed end of the hollow, curvedspring arm 4 is a movable contact finger 5, adapted to be thrown in orout of contact with the adjustable stationary contact points 6 and 7positioned one on either side of the finger 5 and insulated from thecasing 3, in any suitable manner.

Patented June 1, 1915.

Application filed December 2, 1912. Serial No. 734,546.

The temperature of the inclosure in which my regulator is positioned iscontrolled by a suitable cooling fluid, preferably a brine solution, andthe same is adapted to circulate through a system of piping 8 whichextends around the inclosure in any suitable manner.

The circulation of the brine solution is controlled by suitable valvesassociated with openings in a valve casing 11, and from said valvesextend a common valve stem 12, operated by suitable magnet coils 15 and16, mounted in a' casing 17, supported above the valve casing by therods 18. The magnet coils are connected to each other by a lead 19and-are connected at their ends by the leads 20 and 21 with a suitablesource of electric energy. A lead 22 extends from the finger 5 to thelead 19, contact 6 is connected by a lead 23 to the lead21, and contact.7 is connected by a lead 24 with the lead 20, which construction isdisclosed in Fi 2 of the drawings.

g mercury tube 25, preferably formed of glass, provided with a capillarybore 26 extending through the center thereof and formed with an enlargedbore 27 at its lower end, which communicates at its lower end, as at 28,with an enlarged chamber 29 surrounding the bore 27 is mounted within acasing 30, supported in any suitable manner by the tubing 1, and theenlarged chamber 29 is connected at its upper end with the thermo-coils1 by a small tube 31, and 1' s filled for a portion of its capacity witha fluid 32', preferably mercury, as its high specific gravity producesgreater changes of pressure, for any given vertical movement of thecolumn than would be the case with a lighter fluid.

Fromthe above description it will be observed that as the temperature inthe room in which the device is mounted rises, the alcohol in the thermosystem 1 will be heated and will expand. As the alcohol expands, a

certain portion of it is forced through the tube 31 into the upper endof the enlarged chamber 29, the expanding alcohol forcing the mercury atthe lower end of the tube 28 upwardly in the center of the bore 27 andinto the capillary bore 26 of the tube 25 and the higher the mercury isforced in the bore 26 by the expansion of the. alcohol in thethermo-system, the greater the increase of pressure in the system. Asthe pressure increases in the system 1 it also increases in the hollowspring arm 4, and when it reaches a point suficient to overcome thetension of the spring arm 4, the finger 5 of which is normally out ofcontact with the stationary contacts 6 and 7, the arm will be raised,the finger 5 making contact with 6, as shown in Fig. 3.

The magnet coil 15 now being short circuited and the :coil 16 beingfully energized, the valve stem 12 will be drawn downwardly tanner inthe casing 17 and the valves 9 will be unseated from their openings 10allowing a cooling orbrine solution to circulate through the coolingsystem 8.

The electrical connections from the source of electric energy to themagnet coils 15 and 16 is such that sufiicient electricity is at alltimes circulating through the coil when the finger 5 is out of contactwith the contacts 6 and 7, to maintain the valve stem in either positionuntil it is moved by the short circuiting of one of the coils.

' As the temperature of the inclosure is reduced by the circulation ofthe brine solution through the cooling system, the falling temperaturewill cause the alcohol in the thermo-system 1 to contract, the mercuryalso receding in the capillary bore 26 on the contracting of the alcoholin the system 1, and as the level of the mercury drops in the capillarybore 26 the pressure is reduced in the system. When the pressure in thesystem'has reduced sufficiently, the tension of the spring 4; willovercome the pressure that is tending to expand it and will contract,and the finger 5 carried by the end thereof will break contact with thecontact 6, fully energizing the coil 15 and will make contact with thecontact 7, short circuiting the coil 16; by this action the valve stem12 will be'drawn upwardly in the easing 17 and the valves 9 will beseated in the openings 10, cutting off the circulation of the brinesolution through the cooling system 8.

' A hollow pressure regulating tube 32 communicates with the interior ofthe thermo system 1 and in said tube is mounted a plunger head 33carried on the lower end of an adjustable screw-threaded rod 34, thethreads of which intermesh with suitable threads onthe interior of thetube 32, and by adjusting the plunger in the tube the pressure in thesystem will be regulated, forcing the mercury either high or low in thebore 26 so that it will require a considerable or not much expansion ofthe fluid in the system to force the mercury to such height in the bore26 that it will create sufficient pressure to operate the arm 4.

lit will be observed that by the employment of the pressure regulatingtube 32 the system may be readily adjusted to operate chamber and saidbody of confined liquid, said liquid being operated by variations ofpressure in the thermo chamber for opposing the pressures therein toregulate the operation of said Bourdon tube to make or break theelectric circuit controlled thereby.

2. In aregulating system of the class described, the combination with aBourdon tube, electric circuits controlled by the movement thereof athermo chamber, a connection between said chamber and said Bourdon tube,a body of confined mercury, and a connection between the interior ofsaid thermo chamber and said body of confined mercury, said mercurybeing operated by variations of pressure in the thermo chamber foropposing the pressures therein to regulate the operation of said Bourdontube to make or break the electric circuit controlled thereby,

3. In a regulating system of the class de scribed, the combination witha Bourdon tube, electric circuits controlled by the movement thereof athermo chamber, a connection between said chamber and said Bourdon tube,means insaid chamber for regulating the pressure therein independentlyof the rise or fall of temperature around said chamber, a body ofconfined liquid, and a connection between said thermo chamber and saidbody of confined liquid, said liquid being operated by variations ofpressure in the thermo chamber for opposing the pressures therein toregulate the operation of said Bourdon tube to make or break theelectric circuit controlled thereby.

4:. In a regulating system of the class described, the combination of a"Bourdon tube, electric circuits controlled thereby, a thermo coil, aconnection between said coil and said tube, vertically disposed a tubeprovided with a capillary bore terminating at its lower end in anenlarged bore open at its lower end and surrounded by an enlargedchamber adapted to contain a body of mercury, and a connection betweenthe interior of said thermo coil and said last mentioned chamber,whereby the height of the body of mercury in said capillary bore isregulated by variations of pressure in the thermo coil, and said mercuryas it rises and falls in said capillary bore opposing the pressures insaid fall of temperature around said coil, a vertically extended tubeprovided with a capillary bore terminating at its lower end in anenlarged bore open at its lower end, and surrounded by an enlargedchamber adapted tocontain a body of mercury, and a connection betweenthe interior of said thermo coil (and said last mentioned chamber,whereby the height of the body of-mercury in said capillary bore isregulated by variations of pressure in the thermo coil to regulate theoperation of said Bourdon tube to make or break the electric circuitcontrolled thereby. In testimony whereof I have signed my name to thisspecification in the presence of two subscribing witnesses.

GEORGE N. BLANCHARD. Witnesses:

HARRY A. TOTTEN, D. B. RICHARDS.

